Truing device for abrasive wheels used in producing ground articles



L. R. HEIM 1,772,544

TRUING DEVICE FOR ABRASIVE WHEELS USED IN PRODUCING GROUND ARTICLES Aug. 12, 1930.

4 Sheets-Sheet Original Filed Feb. 16, 1925 ATTORNEY Aug. 12, 1930.

L. R. HEIM TRUING DEVICE FOR ABRASIVE WHEELS USED IN PRODUCING GROUND ARTICLES Original-.Filed Feb. 16, 1923 4 Sheets-Sheet INVENTOR MM. Mm

ATTORNEY L. R. HEIM Aug. 12, 1930.

TRUING DEVICE FOR ABRASIVE WHEELS USED IN PRODUCING GROUND ARTICLES Original Filed Feb. 16 71925 4 Sheets-Sheet w f A INVENIOR WEAW ATTORNEY Aug. 12, 1930. L. RHEIM 1,772,544

TRUING DEVICE FOR ABRASIVE' WHEELS USED IN PRODUCING GROUND ARTICLES Original Filed Feb. 16, 1923 4 Sheets-Sheet 4 Wm}. WM

ATTORNEY VENTOR Patented Aug. 12, 1930 um EosT Es PAT NT o FicE LEWIS n. HEIM, or MOUNT noun, FLORIDA, ASSIGNOR, BY MESNE essrenmnn'rs, 'ro

OHIO

meme DEVICE FOR ABRASIVE wHEELsusEn IN P'Ronucme GROUND ARTICLES .tical construction, of wide range of use and having a high degree of flexibility of operation in order thereby to be adaptable to the wide range of various requirements of prac tical use. I

Another object is to provide grinding apparatus of efficient action, and more particularly to provide .apparatus'for readily and conveniently giving. the abrasive wheels of the grinding apparatus the desired con formation to meet various-requirements of practical use.

Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, arrangements of parts, and in the several steps and relation and order of each of said steps to one or more of the others thereof, all as will be illustrat'ively described herein, and the scope of the application of which will be indicated in claims. y

In the accompanying drawings, in which is shown one of various possible embodiments of the mechanical features of this invention,

Figure 1 is a front elevation; and

Figure 2 is a plan view of theapparatus shown in Figure 1, certain parts being broken away in each of these views in order to show certain features of construction more clearly.

Figure 3 is a. plan view on an enlarged Figure 4 is a detached view of certain parts.

of the apparatus shown in Figure 3, this View the following Application filed February 16', 1923, Serial No. 619,373. Renewed September 24, 1929.

construction more clearly.

being partly sectional in order'to the Figure 5 is a sectional view taken line 5-5 of Figure 4.

Figure 4 is a plan view of a modifiedforrn paratus shown in Figure 4 and 11 Figure 4 1s a llke View showing modified form.

' Figure 6 is an end elevation of the Ii1ec'ha-, nlsm shown in Figure 3 and as viewed fromthe right-hand end of this figure.

Figure 7 is a diagrammatic "view illustrative of the action of one of the wheel truing devices upon one of the abrasive wheels the apparatus.

S1m1lar reference characters refer to similar parts throughout the several views of the drawings. v

Referring-now to the drawings andmore particularly to' Figures 1 and 2, there is shown a supporting frame 10 having mounted thereon in suitable ways 11 and 12, respectively, the carriages 13 and 14. The carriage 13 supports suitable bearings 15, in which is rotatably supported a shaft 16 having mounted on its one end a grinding wheel 17 composed of any suitable abrasive material. The carriage 14 supports the spa'ced bearings 18, in which isrotatably mounted the shaft 19 upon the outer end of which is (LINCINNATI, OHIO, A. CORPORATION OF Y.

on the of one of the controlllng elements of the a another mounted a regulating wheel 20 for coaction with the grinding Wheel 17 The wheel 20 may conveniently be, and preferably is, composed of a suitable abrasive material.

Referring now to Figures 1, 3 and 6, it will be noted that'upon the upper part of the carriage 13' and extending in a direction transverse of the axis of the shaft 16 of the grinding wheel 17 there are suitably formed or secured thereto. ways 53 adapted to slidably support an auxiliary frame 54 suitably formed upon its underside to coact with the ways 53. At the right-hand end of the ways L.

53 is formed a vertically extending post 55. in which is rotatably supported and held therein against axial movement a screw 56 in threaded engagement with the auxiliary frame 54. A hand wheel 57 vmounted upon the exterior end of the screw 56 and provided: with graduations 57 serves to per mit control of the auxiliary frame 54 in its I sliding movement along the ways 53.

At the forward-end of the frame 54 (as viewed" in Figure there is preferably formed integrally therewith a sleeve-like housing or bearing portion 58 extending transversely of the ways 53 and of substantial extent in order to support both slidably Figure 4). i

and rotatably a tool-supporting member 59, which may conveniently take the formof a substantially cylindrical'bar or arbor-(see Referring'now to Figure .2 of the drawings, it may at this point be noted that the ways 53 are so formed and related that the axisof the sleeve member 58 is substantially parallel "to the axis of the shaft 16 of the grinding wheel 17 and it pwill-thusbe seen that, assuming that the worksupport 48 is positioned so that the path of travel provided thereby for the work is' in the horizontal plane, the

tool-supporting member 59 in its slidable movement within the sleeve member 58 will be carried in a direction substantially par-' allel to the path of travel of the work along the carrier 48. The tool-supporting, member 59 is slotted at.its right-hand-end, as viewed in Figures 3 and'4, in order to receive therein atool holder 60,uin the lower end of which (see Figure 6) is suitably supported a suit able truing or abrading tool61, preferably taking the form of adiamond. The tool holder 60 may be clamped .in position as by means of the set screw62. Thus it willbe seen that upon slidable 'movement of the tool-support ing member 59 within the sleeve-like member 58 the diamond truing tool 61'will partake. of v a like movement in the generald'irection o that the truing tool 61 may be moved, upon such a slidable movement of the member 59 the axis ofthe memberf59. 1

Referring now to Figure 2, it will be seen within the sleeve-like member 58, across the a point substantially dlametric'ally opposite operative surface of the 'grindin wheel '17, and itwill moreover be'noted, re erring now toFigure 1, ,thatfthe truing tool or diamond 61 is operative on' the grinding wheel 17 at the work support 48.- v

The left-hand portion of the tool-s'upporting member59, as viewed in Figures 3 and 4,

. is provided with a rack 63 integrally formed thereon and ofsubstantialextent, and mesh ing with the rack 63 is the gear 64'mounted upon the verticallyextending stud shaft 65 supported in the bearing66 integrally formed with the auxiliary frame 54. The upper end of the shaft carries a worm wheel 67 with which meshesthe worm 68 (see Figure 3-) carried upon one end of the shaft 69, which is rotatably supported in the bearing member 70 integrally. formed with the bearing portion-66 and extending transversely thereof. The. opposite end of the shaft 69 carries a I hand wheel.71 provided with-a handle .72 t5- permit manual operation of the shaft 69 and hence-of the worm 68. Thus a continuous rotation of theshaft 69 manually bythe handle the face of the grinding wheel 17 is thus assured and thus makes possible a uniform truing or turning down of the operative surface of the wheel.

Referring to Figures 3 and 4, it will be noted "that I prefer to make the rack 63 on the tool-supporting member 59 in the form of a thread, thus not only facilitating the construction but also insuring a reliable and dependable driving connection of the cylindrical bar 59 with the gear 64 irrespective of whatever degree of rotary movement isv given to 5 the bar 59 during its longitudinal movement.

1 As will be seen in Figure 6, the tool holder 60 in which the'abrading tool 61 is mounted supports the tool 61 in a position withrespect to the member 59 such that the abrading tool 61 .is displaced vertically from the axis of the bar 59. It will thus be seen that a rotary movement or displacement of the bar 59 within the sleeve member 58'will thus bring about a movement of the tool 61 in a direction toward or away from the operative surface of the grinding wheel 17.

At the left-hand end of the tool-supporting member 59, as viewed in Figure 4, the latter carries a vertically'extending post or follower 7 3 extending upwardly through the slot 74 of substantial width in the upper part of the sleeve member 58 and extending longitudinally thereof throughout a substantial extent (see also Figure 5). i

Referrlng now more particularly to Figure 5, the sleeve member 58is extended laterally and vertically on each side of the slot 74 to'p'rovide a substantially horizontal supporting surface 58 on one side ofthis slot 74" and -*a substantially similar supportin surface 58 upon the other side thereof. pen

the supporting surface 58 ispositioned a plate member 75 held inposition thereon as by the screws76 and-77 threaded into the sleeve member 58 and extending through the transversely extending'slots 7 5 and 7 5", re-

spectively, in the plate member 75. The plate member 75 is provided with a cam surface 75, shown in Figure 4 as being substantiallya plane surface, and with this cam surface 7 5 the post or follower 73 is adapted to coact.-

As shown in Figure4, the cam plate 75 is adjusted with respect to the sleeve member 58 I so that the plane surface 75 thereof is substantially parallel with the axis of the sleeve member 58. Thus upon a'movement of the bar 59 to the right, a viewed in Figure 4, the follower 7 3 is guided in a substantially straight line direction coincident with the,

axis of the member 59 and a rotation of the member 59 about its axis in'counterclockwise direction, as viewed in Figure 6, thus prevented. In order to insure and maintain a cooperative engagement of the follower 73 with the cam surface 75 of the cam plate 7 5, there is supported upon the supporting surface 58 (see Figure 5) of the sleeve member 58 a plate member 78 as by the cap screws 7 8" and 78 passing through transversely extending slots 78 and 7 8 respectively, in the plate 78. The cap screws 78 and 78" thus guide the plate member 78 in its slidable movement toward the follower- 73, and suitable springs 78 housed in suitably formed recesses in the vertically extending portion 58 of the sleeve member 58 bear against the plate 78 and urge it toward the follower 73.

Suitable screws 7 8 bearing against the outer ends of the spring 78 are adapted to adjust the action of the spring 7 8 ,Thus the follower 78 is securely held in cooperative engagement with the cam surface 75 of the cam plate 75 during its movement with respect thereto, and as above noted and with the parts adjusted as shown in Figure 4, the resultant path of movement given the truing 61 will berectilinear.

The cam plate 75, however, may be adjusted so that its straight-line edge 75 may cause a displacement of the follower 73 as it travels from left to right, as viewed in F igure 4, and hence to bring about a change in the rectilinear path otherwise given to the truing tool 61. Thus in the vertically ex,- tending portion 58 (see Figure 5) of the sleeve member 58 there are provided at its respective ends adjusting screws 7 9 and 7 9 abutting against the cam plate 75. By means of the screws 79 and 79 the cam plate may be adjusted to bring its edge 75 out of, parallelism with the axis of the member 59 and may, for example, be adjusted and then looked in adjusted position by the screws 76 and 77 so that its edge 75 assumes the dotted line position indicated at 75.

gcrews 80 and 80 (see Figure 4) may be ad usted to position the plate 75 so that its cam edge or surface 75.is alined with the axis of the member 59 in order thus to permit a ready andconvenient return positioning of the plate 75 after the adjustment made by the screws 7 9 and 7 9 is dispensed with.

Upon operating the hand wheel 71 to movethe member 59 to the right, as viewed in Figure 4, and thus to carry the truing tool 61 across the operative. surface of the grinding wheel 17, as viewed in Figure 2, for example, the resultant movement of the tool-supporting member 59 in a path of travel substantiallyparallel with the path of travel of the work on the'work support 48 (as hereinbe .the operative surface of the grinding wheel 17, thus varying the action of the tool 61' upon the wheel and hence turning the operative surface of the wheel down to a form or shape conforming to the shape of the path of movement thus given the tool 61. With the adjustment hereinabove assumed, the wheel is given a tapered form to adapt it for taper grinding, for example.

lit will be understood that a substantially similar and. symmetrically built mechanism indicated generally at 81 (see Figures 1 and 2) is provided for operation upon the surface of the regulating wheel 20.

.Where there is no relative inclination be: tween the path of travel of the operative surface of the grinding wheel with respect to the path of travel of the work along the support 48, as has been hereinabove assumed in con-- nection with the adjustment of the truing apparatus shown in full lines in Figure 4,

the operative surface of the wheel is a sub- I sta ntially cylindrical or conical surface; and,

hence where it is desired to true a wheel or wheels under these circumstances, the cam plate'75 isprovided with a cam surface or edge 7 5 shaped to give the follower 63, and hence the truing tool 61 a path of travel that is substantially rectilinear or a straight line. Where, however, there exists a relative inclination between the path of-travel of the op-.

erative surface of either the grinding wheel or the regulating wheel with respect to the path of travel'of work along the carrier 48, the path of contact of the Work with the surface of thewheel is, of course, a straight line,

but the surface of the wheel may be either slightly concave or convex. This is true where the path of travel of the operative surface of the regulating wheel-20 is inclined with respect to the path of travel of work along axialmovement of the work along the sup port and the regulating wheel surface is,

therefore, slightly concave. This concavity of the surface, while slight, is of fixed degree where the relative inclination is fixed in the the support 48in order to effect a feeding or support 48 isthus tilted outof the preferred horizontal position therefor, there results a, relative inclination between the path of travel of the operative surface of the grinding wheel 17 with respect to the path of travel of work" along the support 48, Thus the surface of the grinding wheel may be slightly concave or convex as a result.

In order to true the surface of operated upon by the truing device to the desired shape or conformation and thus, for

example, to give it a concave form, the cam plate 75 may be replaced by one whose cam surface or edge will vary the rotative displaceshaped substantially complementary to the shape or form desired to give the wheel, and the edge 7 5", being downwardly convex, as viewed in Figurea controls the rotative displacement of the tool-carrying member 59 throughout its movement so as to carry the truing tool 61 in a path of movement across the surface of the wheel as will result in giving the latter a concave form.

In Figure le -there is shown, by way of further example, a cam plate 7 5 which may be employed and having a cam surface or edge .75 concavejd upwardly, 'as' viewed in this figure, and adapted thereby to I control the path of movement of the truing tool 61 across the face of its associated wheel to give the latter a convex form. It will be understood, however, that the modified forms of cam plates shown in Figures 4 and P are merely illustrative of possible constructions and that the cam edge or surface of the cam plate may be given any desired shape or form corresponding to or complementary to the shape or form desired to be given the wheel operated upon. Moreover, the modified forms shown in Figures 4 and 4 are merely illustrative of the conformation of the cam surface which may be employed to give the regulating wheel and the grinding wheel the I requisite shapes corresponding to the various conditions of adjustment of the grinding apparatus hereinabove set forth.

As has already hereinabove been noted and as indicated in Figure 1 of the drawings, the

truing devices associated with the respective wheels 17 and .ZOare positioned substantially diametrically opposite the work support 48.

In this connection it should be noted, however, that, as clearly shown in Figure 6, the tool holder 60-is adjustable vertically with respect to the tool supporting and moving member 59.

Referring now to Figure 7, in which the regulating. wheel 20, the work support 48 and the grinding wheel 17 are diagrammatically shown,- itis to be noted that where the wheels 17 and 20 are adjusted to operate upon work of a given diameter as indicated at 82,

the wheel" the lines of contact vor the paths of contact of the work 82 with the respective wheels may be brought into parallelism by the apparatus and mechanisms hereinbefore described, but that in order to effectively bring these paths of contact into parallelism under certain conditions, it maybe desirable to have the path of travel of the truing tool or diamond 61 spaced substantially 180 from the actual path of contact of the surface of the wheel with the work. Thus in Fig. 7 the truing tool 61 is'adjusted vertically with respect to the tool-supporting and moving member 59 so that the path of travel of the diamond or abrading tool 61, a point on the axis of the wheel operated upon, and the path of contact of the wheel with the work lie in the same plane indicated by the line AB. This adjustment is preferablybrought about by adjusting in a vertical direction the tool holder 60 with respect to the member 59 (see Figure 6) and is important where there exists a relative inclination.

If, however, the wheels 20- and 17 are adjusted with respect to one another to accommodate'therebetween work of larger diameter, for example, as indicated at 82 in Figure 7, the path of contact of the work 82 tangency of the work 82 and 82 with'respect I to the regulating wheel 20 indicate diagrammatically this difference in the relativejpositions of the paths of'contactas the wheels.

are adjusted for different diameters of work. In order, then, to true the wheels to present new parallel paths of contact to the work,

the truing tool or diamond 61 is loweredwith respect to-its supporting member 59 so that its path of travel, a point on the axis ofjthe wheel, and the path of contact of the work 82 with the Wheel 20 lie substantially in the same plane indicated by the line 0-1). Preferably the tool holder 60 is provided with graduations indicated diagrammatt' cally at 83 (see Figure 6) whereby the setting of the truing tool or diamond 61 for a given diameter of work and with a given fixed position of the work support 48 may be at once determined; Thus it will be seen that the adjustment of the work support need not be disturbed and that the truing. of the wheels to present the desired parallel paths of contact for whatever conditions of use or adjustment of the apparatus may be readily and conveniently brought about.

Referring to Figure 3. it will be noted that the underside of the sleeve member 58 is slotted as at 84 throughout a substantial longitudinal extent, and there are also provided clamping screws 85 adapted to draw together the portions of the sleeve 58 on opposite sides of the slot. Thus the sleeve 58 may be in effect contracted in order to take up wear and thus to provide for a dependable and rem prevents the coacting bearing surfaces from being exposed. horelgn matter and particularly the emery or other particles from the.

wheels are thus prevented from entering the operative mechanisms and from detrimentally aflecting the coacting bearing surfaces.

Also it will be seen, referring now to Figure 6, that a bell-shaped member 87 not only encases the worm wheel 67 but also forms a pettlcoat over the bearing 66 and thus effectively protects the coacting mechanisms, Thus acdetermine the shape curacy of control and movement is eflectively unimpaired. I

As will be seen in Figures 4 and 5, the follower 73, which coacts with the cam plate to of the path of travel of the abrading tool spherical members 73 and 73*, preferably hardened and conveniently taking the form of balls, in order to present substantially a point contact to the coacting surfaces of the cam plate 7 5 and its cooperating plate 78. Thus the plates 7 5 and 7 8 are preferably also hardened, and it will thus be seen that an accurate, durable and reliable mechanism is provided for predetermining or controlling the shape of the path of travel imparted to the truing tool 61.

The lower end of the tool holder 60, referring now to Figure 6, is extended preferably downwardly adjacent the inserted .truing tool and has formed'therein a nozzle 88, the right-hand end of which, as at 88; is provided with a nipple in order to. facilitate the passage thereto, as by means of a flexible tube 89 (see Figure l), of a suitable cooling fluid such as water from any suitable source of Supply. 7 The nozzle 88 thus directs the cooling tfluid into the region of direct action of the tool 61 upon the wheel, and it will be 7 a e noted that whatever movement or adjustment is given the tool 61, the stream of cooling fluid directed by the nozzle 88 is maintained at its most eflective point of action.

The protective casing 42 in which the wheels 17 and 20am housed (see Figure 1) 18 preferably extended as at 42 to accommodate the truing apparatusoperative upon the grinding wheel 17 and as at 42 to accommodate for movement therein the truing device operative upon the regulating wheel 20. A suitable aperture as at 4:2 is provided for maintaining the connection of the nozzle 88 'Wlth the source of supply of cooling fluid.

It Wlll thus be seen that there has been provided in this invention an art and appaartus 61, is provided with in which the several objects of this invention as well" as many advantages are effectively achieved. It will be seen that the apparatus is of great flexibility of adjustment and that y it is, therefore, readily adaptable to meet the widely varying requirements of practical use Moreover it will be seen that the apparatus. is of durable and, practical construction throughout-and well adapted for highly accurate and precise action.

As various possible embodiments might be made of the mechanical features of the above invention and as the art herein described might be varied in various parts, all Without departing from the scope of the invention, it is to be understood that all. matter herein set forth or shown in the accompanying drawings is to beinterpreted as illustrative and not in a limiting sense.

ll claim" as my invention:

1. In apparatus of the character described, in combination, a member mounted adjacent an abrasive wheel adapted to be moved along a predetermined path transversely of the operative surface of said wheel and mounted to be rotated during said movement about an axis substantially parallel to its line of movement, a truing tool, means mounting said tool on said member to be moved across said wheel and in a position displaced vertically with respect to the axis of rotation of said member, and means having a surface of predetermined shape extending in the general direction of travel of said member and a follower associated with said member co-actrotative displacement of said member during its movement along said predetermined path and as said tool moves across said wheel, and

rotatable threaded means for moving said member in its path of travel.

2. In apparatus of the character described,

in combination, a tool-supporting member,

means for slidably and rotatably supporting said member and adapted to provide a path of travel therefor substantially transversely of the operative surface of an abrasive wheel, a truing tool mounted upon said member and displaced from the axis of rotation thereof to permit, upon a rotative displacement of said me'mber a movement of said tool in a direction toward or away from the operative surface of said wheel, means havin a surface of predetermined shape and exten ing in the general direction of travel of said tool-sup porting member, and a follower associated with said member and formed to have a point contact with said surface to control the degree of rotative displacement during the movement of said member.

3. In apparatus of the character described, in combination, a tool-supporting member, means for slidably and rotatably supporting said member and adapted to provide a path of travel therefor substantially transversely of the operative surface of an abrasive wheel, a truing tool mounted upon said member and displaced from the axis ofrototion thereof to perm1t, upon a rotative displacement of said member a movement of said tool in a direction toward or away from the operative surface of said wheel, means having a surface of predetermined shape extending in the general direction of travel of said member, a follower associated with said member coacting with said surface to control' the degree of rotative displacement during movement of said member, and means adjustably mounting said last-mentioned means to perber and adapted to provide a path of travel mit the relation of said surface of predetermined shape with respect to the directionof travel of said member to be varied at will, and

rotatably threaded means for moving said member in its path of travel.

4. In apparatus of the character described,

in combination, a truing tool, means mountmg said tool in operative relation to the surface of anabrasive wheel and adapted'to be moved in a path substantially transversely of 5. In apparatus of the character described,

in combination, a tool-supporting member having associated therewith a rack, means for slidably and rotatably supporting said memtherefor substantially transverse of the operatlve surface of an abrasive wheel, a gear meshing with said rack adapted upon rotation to move said tool-supporting member, a v tru ng tool mounted upon said member in a position displaced from'the axis of rotation thereof to permit a movement of said tool in a direction toward or away from the operative surface of said wheel upon rotation of said member, and means for controlling the degree of rotative dlsplacement of said member during its movement by said gear,

' 4 having associated therewith a rack, means for i ative surface of an abrasive wheel, a gearv meshing with said rack adapted upon rotation to move said tool-supporting member, a trumg toolmounted upon said 'member in a *position displaced from the axis of rotation thereof to permit a movement, of said tool in a direction toward or away from the operat ve surface of said wheel 'upon rotation of' 6. In apparatus of the character described, in combinatlon, a tool-supporting member slidably and rotatably supporting said member and adapted to provide a path of travel thereforsubstantially transverse of the oper said member, a follower mounted upon said member, and a cam plate mounted upon said supporting means, said follower co-actmg with said cam plate to control the degree of rotative displacement of said meniber during the movement thereof in response to said ear.

b 7 In apparatus of the character described,

tool-supporting member, a sleeve member substantially enclosing said cylindrlcalmember for slidably supporting said member and adapted to provide a path of travel therefor substantially transverse of the operative surface of an abrasive wheel, said sleeve member being slotted in the direction of its length, a truing tool ing member and adapted to be carried thereby across the operative surface of said wheel, and means for adj ustably clamping the slotted portions of said sleeve toward oneanother to take up wear.

8. In apparatus of the character described,-

in combination, a member having a substantially cylindrical outer surface and mounted adjacent an abrasive Wheel to be moved lengthwise of its longitudinal axis and in a direction transversely of the operative surface of said wheel and mounted to be rotated about its longitudinal axis, a truing tool mounted upon said member and spaced from mounted upon said tool-support [in combination, a substantially cylindrical said axis thereof and adapted to be carried thereby across the wheel surface, and templet means to swing said member about said axis and thereby move said tool in a direction toward and away from the wheel surface as said member moves and as said tool operates upon thewheel surface.

9. Inapparatus of the character described,

in combination, a member having a substantially cylindrical outer surface, means mounting said member adjacent an abrasive wheel for turning aboutit's axis and for movement substantially lengthwise of its axis, a truing tool carried by said member and spaced from said axis, means for giving said member said lengthwise movement to carry said' tool across the operative surface of said wheel, and an arm projecting sub- A stantially radially from said member and adapted to be guided as said member moves to determine the angular position of said tool with respect to said axis. 1

10'. In apparatus of the character described, in combination, a member having a substantially cylindrical outer surface, means mounting said member adjacent an abrasive wheel for turning about its axis and for movement substantially lengthwise of its axis, a truing tool carried by said member and spaced I from said axis, means for giving said member said lengthwise movement to carry said tool across the operative surface of said wheel, an arm pro jecti'ng substantially radially "from said ber and spaced from said axis, means for giving said member said lengthwise movement to carry said tool across the operative surface of said wheel, an arm projectlng substantially radially from said member, and a pair of guiding surfaces between which said arm moves adapted to control the rotation of said member about its axis.

12. In apparatus of the character described, in combination, a truing tool, a member in which said tool is mounted and having a cylindrical portion, a bearing in which said cylindrical portion is supported to mount said member for rotativemovement and for movement lengthwise of its-axis to carry said tool across the surface of an abrasive wheel, said truing tool carried by said member being spaced from the axis of rotation of said member, means for giving said member said lengthwise movement in said bearing, a part secured to saidmember and projecting therefrom in a direction transversely of its axis, and a surface across which said part moves for controlling the angular position of said member about said axis. 13; In apparatus of the character de-' scribed, in combination, a truing tool, a member in which said tool is mounted and hav-' ing a cylindrical portion, a bearing in which said cylindricalportion is supported to mount said memberfor rotativemovement and for movement lengthwise ofits axis to carry said tool across the surface of an abrasive wheel, said truin tool carried by said member being spaced rom the axisvof rotation of-said member, means for giving said member sald lengthwlselmovement 1n said bearing, a part secured to said member and projecting therefrom in a direction transversely of its axis, and a pair of guidin surfaces between which said'part moves, sai

surface being adjustable in position and re- J movable for replacement by surfaces of other shapes.

14. In apparatus of the character described, in combination, a truing tool, a member in which said tool is mounted and having a; cylindrical portion, a bearing in which said cylindrical portion is supported to mount said member for rotative movement member being spaced from the axis of rotationof said chamber, means for giving said member said lengthwise movement in said bearing, a part secured to said member and projecting therefrom in a direction transversely of its axis, a pair of guiding members between which said fart moves, and spring means urging one 0 said guiding members toward the other.

In testimony whereof, I have si ed my name to thisspecification this 2n day-0f February, 1923.

- LEWIS R. HEIM.

and for movement lengthwise, of its axis to carry said tool across the surface of an abra sive wheel, said truing toolcarried by said Cal CERTIFICATE OF-GORRE'GTIORQ l atent No. 1,-772,s44.f J Granted August 12, 1930, 0

LEWIS R. .HEVIIM.

I Ibis hreby nrtified that error appears the. printed specification of the :above numbered patentrequiringnporreption as follows; Page 7,. line 67, claim 14, fqrthe 'word chamber" readmemben and that the said- Letters Patent shot 11d be read with this com'ction therein that the' same may cphform to the record of ,,th case in the Patent Officer I 7 v v Signed and sealed this 4th day 'of November; A. 1930.-

, M.J.Moore,

(Seal) t Acting Commissioner of.P atents. 

